21879

素因数分解:

$3^2\times {\mathrm{11}}^1\times {\mathrm{13}}^1\times {\mathrm{17}}^1$

素因数の和:47

約数の個数: 24

約数和(自身を含む): 39312

約数和(自身を除く): 17433

約数列:

[1, 3, 9, 11, 13, 17, 33, 39, 51, 99, 117, 143, 153, 187, 221, 429, 561, 663, 1287, 1683, 1989, 2431, 7293, 21879]

約数ペア:

[(1, 21879), (3, 7293), (9, 2431), (11, 1989), (13, 1683), (17, 1287), (33, 663), (39, 561), (51, 429), (99, 221), (117, 187), (143, 153)]